What is the difference between hard real-time and soft real-time OS?
A hard real time system guarantees that critical tasks complete on time this goal requires that all delays in the system be bounded from the retrieval of the stored data to the time that it takes the o.s to finish any request made of it. A soft real time system where a critical real time task gets priority over other tasks and retains that priority until it completes.As in hard real time system kernel delays need to be bounded. 19. What type of scheduling is there in RTOS? In typical designs, a task has three states: 1) running, 2) ready, 3) blocked. Most tasks are blocked, most of the time. Only one task per CPU is running. In simpler systems, the ready list is usually short, two or three tasks at most. The real key is designing the scheduler. Usually the data structure of the ready list in the scheduler is designed to minimize the worst-case length of time spent in the scheduler’s critical section, during which preemption is inhibited, and, in some cases, all interrupts are disabled.
